The temperature dropped below freezing yesterday morning, and there were those columnar ice crystals again.
I surfed the web last year to learn more about them, but failed to find anything.
Technically, this kind of ice may not be frost since it is formed from water in the surface soil.
The reddish brown tint of the ice is due to soil particles that were lifted on top of the columns as they formed.
Does anyone know what this kind of ice formation is called?
(Does anyone, besides me, care?)